MANILA—The Philippines government said Tuesday a previously unknown group that allegedly attempted to smuggle an improvised bomb into Manila's international airport also planned to attack other targets in the capital, including the Chinese Embassy.

Justice Secretary
Leila de Lima
said the government was preparing to charge three men who were arrested by the National Bureau of Investigation in the airport parking lot early Monday. She said NBI operatives found an improvised incendiary device in the suspects' van that they believe was intended to bomb the airport.

Ms. de Lima said the suspects are from an anti-Chinese group called Usaffe. She said they were arrested following a tipoff by an informant, who claimed attacks were also planned on SM Mall of Asia, a DMCI office building, and the Chinese Embassy in the financial district Makati. SM Mall of Asia and property developer
DMCI Holdings
are owned by Filipino-Chinese tycoons.

None of the three alleged targets have commented on the arrests. The NBI is investigating if more people were involved in the alleged plans, the justice secretary said.

She said the three suspects would be charged with illegal possession of a firearm and an incendiary device. The charges carry a maximum prison sentence of 12 years. The men may also be charged with conspiracy to commit terrorism, depending on evidence, she added.

Ms. de Lima described Usaffe as a misguided group frustrated by what it thinks is a weak stance by the government on China. The main disputes between the Philippines and China are over territories in the South China Sea.

She identified the arrested men as Sonny Diojanon, Emmanuel San Pedro and
Pepito Guerrero.
Justice authorities say Mr. Guerrero claims to be a general of Usaffe.

The police and the military have played down the threat posed by the group.

"This is not a terrorist attack," General
Gregorio Pio Catapang,
the Armed Forces Chief of Staff, told reporters at a briefing. Col.
Reuben Theodore Sindac,
national police spokesman, said the police have no information of a terror plot.

"We will leave it up to the discretion of the regional directors to raise their security alert level as they deem necessary," he said.

The three suspects at the Department of Justice on Tuesday.
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